IMPERIAL 

Weldings Cutting 

HAND BOOK 




THE IMPERIAL BRASS MFG.CQ 
1200 W.HARRISON ST.CHICAffiO 



IMPERIAL 

We laing and Cutting 

HAND BOOK 



OXY-ACETYLENE 
OXY-HYDROGEN 
CARBON BURNING 



Price, $1.00 per copy 



The Imperial Brass Mfg. Co. 

1200 West Harrison Street, .... Chicago 



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Copyright 1916 

by 

The Imperial Brass Mfg. Co., Chicago 



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AUG 24 1916 



©CI.A43.6 510 



THE IMPERIAL BRASS MFG. CO. 



PREFACE 

With proper or intelligent use, Imperial Apparatus is practically 
indestructible. So far as engineering knowledge, carefully selected 
materials, modern machinery and skilled mechanics can make them, 
the regulators, gauges, torches and other parts which comprise the 
equipment, are built for service — to give the proper kind of a flame 
and to stand up under ordinary wear year in and year out. 

We have done our part ; but unless you acquire an elementary 
knowledge of the apparatus, its use and how to properly keep it in 
good working condition, the best possible results cannot be expected. 
To give this necessary elementary knowledge is the purpose of this 
booklet. Its careful reading will help to effect a better understanding 
of Imperial Equipment and its use and will probably save annoying 
mistakes, due to lack of knowledge. 

The text is free from technical verbiage and while volumes could 
be written on the subject, we believe this covers the fundamentals. 
Following along the lines described, the operator will be on the way to 
becoming a successful user of oxy-acetylene equipment. 

Following out the rules and directions of this booklet will make 
your work not only a success but a pleasure as well. 



THE IMPERIAL BRASS MFG. CO. 




SUGGESTIONS FOR BEGINNERS 

NE of the things NOT to do after purchasing an oxy-acety- 

lene welding outfit is to immediately solicit work. Note 

that word immediately. There is no quicker way of hurting 

your own reputation and of giving oxy-acetylene welding a 

general black eye than to fall down on a job for a customer. 

In several instances, novices have solicited work before their 
apparatus arrived. Others, without even connecting the equipment, 
announce they are ready for all the castings of any metal — and into 
the shop come malleable iron, aluminum, bronze and cast iron — metals 
with which the newly enlisted operator is probably unfamiliar, to be 
welded by a process totally different from the method he has been 
acquainted with. 

Now the oxy-acetylene flame will certainly join all these metals, 
but, given the proper equipment, it is essential that some judgment 
and some practice be added. To practice on a customer's job means 
the enmity of that customer. So, before tackling oxy-acetylene on a 
commercial scale, put the apparatus in the back of the shop or in a 
separate room, master the principles and practice on scrap material. 
Then make a noise. 

There are certain fundamental principles which must be under- 
stood and mastered before commercial welding, even upon a simple 
scale, is undertaken. These fundamental principles are given on the 
following pages, but one can't become a welder by reading alone — it 
is necessary to do actual welding, though reading practical articles 
will certainly help. 

Whenever possible, by all means secure some training, a week or 
two, in a repair '-.hop. If this is not possible, practice on junk material 
until you are competent to operate the oxy-acetylene equipment. 



THE IMPERIAL BRASS MFG. CO. 



PRINCIPLE OF WELDING 

Welding with the oxy-acetylene flame is a fusing process. With 
a temperature of over 6,000° F., concentrated in a comparatively small 
point, the flame is held on the edges to be united UNTIL THEY 
MELT TOGETHER. Since by this process, no hammering or com- 
pression is necessary, it is applicable to all the metals: cast iron, malle- 
able iron, steel, aluminum, bronze and copper. 

Oxygen is purchased in conveniently handled cylinders or drums 
which are charged to a pressure of approximately 1,800 pounds. 
Purity is essential to the successful and economical operation of the 
oxy-acetylene process and the oxygen purchased in these high pressure 
drums is considerably cheaper and much purer than that made by 
chemicals on the premises. The proper manufacture and testing of 
both the oxygen and acetylene cylinders is supervised by an U. S. 
Government commission and if ordinary precautions are employed by 
the user, the tank system of gases is ideal. 

Acetylene in tanks is more properly known as dissolved acetylene. 
The cylinder is filled with a porous material and also with a liquid 
known as acetone, which has the quality of absorbing many times its 
own volume of acetylene. Acetylene, in a free state, is dangerous at 
pressures greater than fifteen pounds. Dissolved, however, this hazard 
is removed and the gas in cylinders, while costing a little more than 
that generated on the premises, is considerably purer, is always ready 
for use merely by opening the valve and requires no care. In addition, 
the use of dissolved acetylene makes the entire equipment portable, a 
feature many times of real value for repair purposes. Pressures of 
acetylene cylinders vary with the different manufacturers and tem- 
peratures, but the average is around 225 pounds to the square inch. 

With pure gases, it is necessary that the equipment — that is, the 
regulators, torches, etc. — be scientifically constructed and used with 
intelligence to effect satisfactory results. An understanding of the 
principles of this equipment we believe is essential. As you become 
acquainted with Imperial Apparatus, you will realize with what care 
and precision it is constructed, how the factor of strength has been 
obtained without clumsiness ; how we have removed every danger 
hazard possible except one — the human element — so that we have con- 
sidered it necessary to devote a part of these instructions to the care 
of the apparatus. 



THE IMPERIAL BRASS MFG. CO. 




PLATE 1 

SHOWING IMPERIAL WELDING OUTFIT CONNECTED TO TANKS 

A— Acetylene Inlet to Torch. AV— Acetylene Valve on Torch. B— Tank 
Coupling. C — Hose Coupling. D — Outlet Valve to Hose. E — Acetylene 
Regulating Screw. F — Acetylene Tank Valve. G — Oxygen Tank Valve. H — 
Tank Coupling. J — Hose Coupling. K — Outlet Valve to Hose. L — Oxygen 
Regulating Screw. M — Acetylene Tank Pressure Gauge. N — Acetylene Work- 
ing Pressure Gauge. O — Oxygen Inlet to Torch. OV — Oxygen Valve on 
Torch. P — Oxygen Tank Pressure Gauge. R — Oxygen Working Pressure 
Gauge. 

Note — When either the Searchlight or Commercial Companies' Acetylene 
Tanks are used, the Acetylene Regulator stands out at right angle to the tank, 
as shown in center tank. 

When Prest-O-Lite Tanks are used, the regulator stands up on end, as 
shown in partial view of tank at left. 



THE IMPERIAL BRASS MFG. CO. 



CARE OF APPARATUS 

OXYGEN — The use of a truck for the apparatus is very desirable. 
Even though the portable feature may not be desired, the oxygen 
cylinder should be firmly clamped or strapped to avoid falling. If, 
then, you are not a user of the truck, which secures both cylinders, see 
that the oxygen cylinder is made secure to a wall or bench, for the 
reason that because of its small base, it is very easily tipped over and 
a broken regulator would be the result. 

Keep the cylinders in a reasonably cool place, away from fires or 
the direct rays of the sun, remembering that heat causes the gas to 
expand and while the factor of safety of the cylinder is a big one, it 
pays to be cautious. 

Bear in mind that oil and oxygen under any considerable pressure 
make a very dangerous combination. Oil burns — oxygen is the gen- 
erator and supporter of combustion; therefore, it would be quite a 
simple matter to secure spontaneous combustion through this com- 
bination. NEVER USE OIL ON ANY PART OF THE OXYGEN 
SUPPLY, the tank valve, the regulator, the connections or the torch. 

Before the regulator is attached to the drum, open the valve on 
the cylinder quickly and close it immediately, thus blowing away any 
dirt that may be present on the seat of the outlet valve. If, after 
attaching the regulator, the valve on the drum or cylinder leaks, 
quickly open it as far as possible. If it still leaks, close it and take off 
the regulator and return the cylinder to the manufacturers, with a 
statement of the trouble. DO NOT ATTEMPT TO REPAIR THIS 
VALVE. Remember there is 1,800 pounds pressure per square inch 
behind it and the sudden release of this gas, caused by carelessness in 
repairing the valve, would probably result in an injury to the 
workman. 

This tank valve is provided with a safety in the form of a hex. 





PLATE 2 

Adantor f° r connecting Imperial Acetylene Reg- 
H ulator to Prest-O-Lite 100, 150 and 300- 

foot Tanks 



PLATE 3 

Adaptor f or connecting 
r Imperial Acety- 

lene Regulator to Search- 
light or Commercial Co.'s 
Tanks 



THE IMPERIAL BRASS MFG. CO. 



nut, which is sealed. The connection for the regulator is a male 
thread, without any nut. It would hardly seem necessary to warn the 
user against taking off the safety nut, yet instances have been recorded 
where the workman attempted to do this with very unsatisfactory 
results. LEAVE THE SAFETY ALONE. If it at any time leaks, 
return the cylinder, with a letter of explanation. 

LEAKS — While oxygen itself will not burn, and has no odor, 
leaks should be guarded against, for the reason that oxygen will feed 
a fire with considerable energy. 

TO USE MATCHES OR A FLAME IN FINDING AN OXY- 
GEN LEAK IS HAZARDOUS. Soapy water used with a brush or 
rag may better be employed. 

OXYGEN REGULATOR— As we have already learned, the 
initial oxygen pressure is 1,800 pounds to the square inch, decreasing, 
of course, as the contents of the tank are used. The pressure at the 
welding torch varies from a few pounds on the small tips to eighteen 
on the large size and in cutting reaches 125 pounds. The duty of the 




PLATE 4 

Imperial Oxygen Regulator — Type C 

H— Tank Coupling. J — Hose Connection. K— Outlet Valve to Hose. 
L — Regulating Screw. P — Tank Pressure Gauge showing pressure in tank 
and contents in cubic feet. R — Working Pressure Gauge showing pressure 
delivered to torch. 



THE IMPERIAL BRASS MFG. CO. 



regulator then is to reduce the tank pressure to the amount required, 
to deliver an absolutely steady flow of gas at this pressure and to 
maintain the necessary volume, irrespective of the tank pressure. 
Imperial regulators will do all these things and keep doing them if 
they are properly treated. 

Note carefully the explanation following and so avoid the troubles 
of those not understanding what an oxygen regulator is. 

The principle of operation is very simple. After the regulator is 
attached to cylinder and the tank valve has been opened, the flexible 
metal diaphragm is interposed between the pressure of the cylinder 
and the heavy springs, the tension of which may be set at the pressure 
desired by means of the regulating screw. If, for instance, the pres- 
sure of the gas desired is twenty-five pounds, the regulating screw is 
turned to the right and the springs forced against the diaphragm to 
this tension, which will so register on the small gauge directly over 
the body of the regulator. As the gas enters the body of the regulator 
from the cylinder it passes through the seat and presses up against 
the diaphragm. It will quite readily be seen that whenever the pres- 
sure from the cylinder exceeds the spring tension, the gas pressing 
against the diaphragm will overcome the spring tension, thus forcing 
the diaphragm outward (against the springs) and as the plunger of 
valve is attached to the diaphragm, it is drawn against the seat of 
valve and the gas from the cylinder shut off. 

The oxy-acetylene flame must at all times have a steady, even 
flow of gas. Therefore, the regulator, which is an instrument of very 
delicate manufacture, must be handled carefully by the operator to 
maintain this object. 

Before turning on the gas at the cylinder, BE SURE THAT THE 
SPRING TENSION IS RELEASED, i. e., the regulating screw 
turned to the left, which brings the plunger of valve down onto the 
seat, thus closing the regulator. After opening the tank valve, turn 
the regulating screw to the right until the small gauge registers the 
pressure desired. NEVER TURN ON THE GAS AT CYLINDER 
WITH THE REGULATING SCREW TIGHT, AS THIS PUTS 
SPRING TENSION ON THE DIAPHRAGM and allows the gas 
from the cylinder to enter the body of the regulator very suddenly 
(because the plunger of valve is away from the seat) and as the sud- 
den pressure strikes the diaphragm, the plunger is thrown violently 
against the seat, often causing the seat to become cracked or broken. 

With the motor of an automobile racing, you wouldn't throw the 



10 ___ THE IMPERIAL BRASS MFG. CO. 

gears in mesh for high speed direct from neutral and attempt to start 
away from the curb — not if you want to keep your automobile very 
long — yet turning on the oxygen with the spring tension on the regu- 
lator has about the same effect on the regulator. 

Bear in mind that the regulator is a steadying device — that the 
diaphragm is the balance between the high pressure of the cylinder 
gas and the spring tension and that at all times the movement of this 
diaphragm should be slow — never violent. 

The low pressure gauge (R), Plate 4, is a positive index of regu- 
lator trouble. If you are operating, say at fifteen pounds, and after 
shutting off the valve on the torch, the hand on the dial keeps moving 
to twenty-five or thirty or forty pounds without stopping, it means 
that the seat is damaged — that the high pressure of the cylinder is 
leaking past the plunger of valve and the regulator should be imme- 
diately sent back to the factory for repairs. Only by violating some 
of the rules previously given would you be likely to damage this seat ; 
but once damaged, it should be immediately repaired. 

ACETYLENE — The acetylene cylinder usually has a broad base; 
and, therefore, is not so easily tipped over as the oxygen; yet, even in 
this instance, especially where the smaller tanks are used, it is advis- 
able to have it clamped and the truck is therefore a desirable and a 
wise investment. 

ACETYLENE DOUBLES IN PRESSURE AS THE TEM- 
PERATURE IS DOUBLED— Therefore, keep the cylinder away 
from any excessively hot place. Do not carry this idea so far, how- 
ever, as to keep the cylinder cold, as better and more economical 
welding results are secured with the cylinder in a WARM place ; i. e., 
with a temperature of around 90° F. As the gas is used, and the pres- 
sure decreased, this temperature may be increased without danger, 
especially as in using the gas there is considerable refrigeration, which 
is offset by having the cylinder warm. 

Remember, that besides the acetylene in the tank, there is also a 
very volatile liquid. When the gas in the tank is exhausted, CLOSE 
THE VALVE, as the vaporizing of the liquid and its escape might 
cause an explosive mixture. 

DON'T USE AUTOMOBILE LIGHTING CYLINDERS EX- 
CEPT IN EMERGENCY. They are much more expensive to oper- 
ate than regular welding cylinders and in addition, the liquid absorb- 
ent in the cylinder is liable to be withdrawn, thereby lowering the heat 
of the welding flame and adversely affecting the weld. Acetylene 



THE IMPERIAL BRASS MFG. CO. 11 

should not be used at a rate greater than one-seventh the tank capacity 
per hour. If a tip consumes 20 feet of acetylene per hour and the 
acetylene cylinder used is a 100-foot size, it will readily be seen that 
the rate of withdrawal of gas is much too rapid and a 225-foot size 
should be employed, or if small cylinders only are available, connect 
two or more by means of a manifold, attaching the regulator to the 
manifold, to insure getting the necessary volume of gas without 
drawing out the acetone. 

LEAKS — Acetylene has a decided odor, quickly recognized even 
if the leak is a very small one. If such a leak cannot be located by 
the odor, it is advisable to hunt for it with soap suds, just as when 
looking for an oxygen leak. Should the acetylene ignite around the 
packing nut or between the regulator and the connection, do not be 
unnecessarily alarmed, as the flame will not go back into the tank. 
Simply blow it out and tighten the nut where the gas is escaping, if 
the leak is a small one. The chief danger to guard against is the con- 
tinued escape of gas and its ignition when an explosive mixture is 
formed. Such a condition could only occur through extreme 
carelessness. 

ACETYLENE REGULATOR— The principle of this regulator 
is the same as that used for oxygen, and while the initial pressure to 
be reduced is comparatively small, it is well to be governed by the 
same rules in its care as apply to the oxygen regulator. 

It is equipped with two gauges, one 500 pounds to indicate tank 
pressure and one 50 pounds, showing the line or torch pressure. Note 
that the 500-pound gauge indicates tank PRESSURE, not CON- 
TENTS. This pressure will vary according to temperature ; and a 
cylinder having 150 pounds may have the same cubical contents as 
one having 300 pounds pressure. This is fully explained later in the 
chapter devoted to Figuring Costs, Page 43. 

WELDING TORCH— The Imperial torch is so constructed that 
the factor of strength is considerably greater than in any other on the 
market — this for the reason that a welding torch is very often care- 
lessly handled; if it receives very ordinary care, it is practically 
indestructible. 

The oxygen hose is attached to the upper connection (marked O), 
the acetylene to the lower (marked A). Both are ground joints and 



12 



THE IMPERIAL BRASS MFG. CO. 




PLATE 5 

Imperial Acetylene Regulator — Type AA 

B — Tank Coupling. C — Hose Connection. D — Outlet Valve to Hose. 
E — Regulating Screw. M — Tank Pressure Gauge showing pressure in tank. 
N — Working Pressure Gauge showing pressure delivered to torch. 




€ 



AV- 




OV 



IMPERIAL 



EXTENSION 








10 9 8 6 54321 
PLATE 6 

Imperial Welding Torch — Type B 

A — Acetylene Inlet. B — Removable Welding Tip. AV — Acetylene Valve. 
O — Oxygen Inlet. OV — Oxygen Valve. Nos. 1-10 are the Welding Tips. 



THE IMPERIAL BRASS MFG. CO. 13 

make up easily. The shut-offs are so situated as to enable the opera- 
tor to adjust the flame while welding, with the thumb or fore finger of 
the hand grasping the handle. 

LEAKS— After attaching the hose, see that the connection is 
tight before lighting the torch. Make sure of this, as a leak at this 
point may burn the hand. Then see that the valves are tight and do 
not leak, either open or shut. After continued use, it may be found 
necessary to clean these small valves and to repack. Be careful not to 
use oil and for packing use graphite-asbestos. 

ABUSE OF TORCH— Don't attempt to use the welding torch 
as a pair of tongs in helping to turn a casting while welding. Remem- 
ber that it is constructed of bronze composition and is made to weld 
with — not for use as a crowbar. 

In working on a hot casting, where there is little escape for the 
heat waves, except directly against the torch, keep it cool by having a 
bucket of water handy and SLOWLY immersing the torch, with the 
acetylene shut off and the OXYGEN PARTLY SHUT OFF. Proper 
judgment in this respect will prevent the burning of tips and the 
fouling of the mixing tube, due to heating the mixed gases to the 
ignition point. 

FLASHBACK — Due to the long mixing chamber of the Imperial 
torch and the natural cooling effect of the gases under pressure, the 
flashback is an almost unknown occurrence. Bringing the tip in close 
contact with the metal will not (as it does in most welding torches) 
cause the Imperial to burn back to the mixing chamber. 

There are only two ways in which a flashback will occur — both 
easily prevented by the operator, if he is careful. 

The first is lack of acetylene — that is, giving the flame too lean a 
mixture. The adjustment of the gases is fully explained on Page 21. 
Since good welding can only be obtained with the correct flame, which 
is neutral in character, it behooves the operator to be careful in his 
adjustment and not allow the oxygen to be in excess of the acetylene, 
which would give a lean mixture and so invite a flashback. 

The second is heat. A mixture of acetylene and oxygen will 
ignite at a comparatively low temperature. Therefore, if the torch is 
heated to a fairly high degree, the gases will burn back to the mixing 
chamber. This degree of heat may be obtained by holding the torch 
over a heavy, hot casting (previously described) or by bringing the 
torch in continued close proximity to the metal and causing a snap- 
ping; i. e., the TEMPORARY burning back of the gases. If this 



U THE IMPERIAL BRASS MFG. CO. 

snapping is continued, the tube or mixing chamber eventually be- 
comes hot enough to ignite the mixed gases and a flashback results. 

When a flashback occurs, shut off the oxygen first, then the acety- 
lene and cool the torch. Then relight and adjust the flame, BUT the 
flashback may be almost entirely obviated by attention to the two 
reasons given. It is better to eliminate the CAUSE than to allow it 
to flashback, as the continued burning back of the gases may seriously 
affect the proper regulation of the torch. 

BURNED TIPS — Welding in a corner, or in a depression, where 
there is no escape for the heat waves, except against the torch tip, 
may cause the tip to become heated to such an extent that it will melt. 
By a study of local conditions, we are usually able to plan to avoid 
this by proper manipulation of the torch. If we are not able to do 
this, cool the tip frequently, as a burned tip is not again usable. 

RAGGED TIPS— By flying sparks or molten flux, the end of the 
tip at times becomes partially clogged and the flame then assumes a 
ragged shape. Clean these tips with soft wire or wood, using care 
not to get the aperture out of round. 

CARE OF TIPS — Bear in mind that heat causes metals to ex- 
pand — use care in screwing up or unscrewing the tips while they are 
hot, since carelessness in this respect may strip the thread. Keep the 
tips in a clean place, away from dirt — in the apparatus box or in a 
small rack near the welding table. 

HOSE, GOGGLES, SUPPLIES— Examine the hose at intervals 
for leakage, especially where it clamps to the torch. Either gas leak- 
ing at this point may cause a serious burn. So far as possible, keep 
the hose off the floor away from oil and possible damage by being 
trampled upon. And while welding, see that it is in such a position 
that no one may trip over it, not especially because it will hurt the 
hose, but more for the reason that such an occurrence might mean a 
bad burn to the operator by pulling the torch from his hand. 

It is always necessary to watch each detail of the molten metal — 
keep the welding glasses clean to enable you to do this properly. 
NEVER WELD WITHOUT THESE GLASSES, since to do so 
means an impairment of the vision. 

Welding rods should be kept clean and in a place convenient to 
the operator ; as they become short, weld them together in leisure 
time, to be ready when the job is started upon. Keep the flux cans 
closed when not in use — especially the aluminum, as this absorbs 
moisture from the air and is useless as a flux when this happens. 



THE IMPERIAL BRASS MFG. CO. 



15 



EXPANSION AND CONTRACTION 

As we heat metal, we expand it ; as it cools, it contracts. The 
degree of expansion is not the same with all metals, aluminum expand- 
ing and contracting more than cast iron for instance. 

Different metals CONDUCT HEAT with varying degrees, cop- 
per having the greatest conductivity of the metals we have to deal 
with in welding, so we must take into consideration the expansion and 
conductivity of the metal we are welding in order that we may allow 
for the shrinkage when the metal cools. Since cold metal must occupy 
a smaller space than hot metal, it follows that unless we recognize 
this and plan to offset it in some way, this shrinkage is likely to distort 
the article we are welding or in some cases break it. NOTHING 
CAN PREVENT THE EXPANSION OF METALS WHEN 
HEATED OR CONTRACTION WHEN THEY COOL OFF 
AGAIN. 




PLATE 7 



The effect of expansion and contraction is illustrated in Plate 7. 
Suppose that we weld a bar at the break shown. As we heat it, the 
metal expands ; but there is opportunity for it to expand on the ends, 
since they are free to move, or towards the break, and when the weld 
cools, the ends will move back or perhaps the bar will be slightly 
shorter — it depends upon how much care we have used in setting the 
job up. 



16 



THE IMPERIAL BRASS MFG. CO. 




PLATE 8 

Now, suppose that this bar is the middle member of a frame, as 
illustrated in Plate 8, with the same character of break. Here the 
ends are permanently attached and as we heat the bar at the break, 
the ends being rigidly held, have no opportunity to move and the 
expansion is all toward the break. Since cold metal must occupy a 
smaller space than hot metal, as the metal cools, the middle bar con- 
tracts and shortens and results in breaking the bar or some portion of 
the frame or the distortion of the frame in the general shape as shown 
by the dotted lines. Whether it breaks or bends depends upon the 
DUCTILITY of the metal, i. e., the ability of the metal to stretch. 
Wrought iron or steel, for instance, would probably bend out of shape. 
Cast iron would probably break. Aluminum might break or it might 
bend — it would depend upon the alloy used in the casting. But irre- 
spective of whether the article is broken or bent, it would be consid- 
ered an unsuccessful welding job, even though the weld itself is first 
class. It is, therefore, evident that this must be overcome in some 
manner before we can do successful welding. 

The most common form is to heat the article all over in order to 
set up an equal expansion throughout and consequently have the metal 
cool equally all over. This is not possible in all cases, however, or 
practical. In the figure illustrated, it is not necessary, since we may 
heat the two side bars about as much as we would heat the middle 
bar in welding and thus take care of contraction, since in heating the 
side bars, the break in the middle bar would open up. Perhaps condi- 
tions are such that we are unable to heat either a portion of the article 



THE IMPERIAL BRASS MFG. CO. 17 

or all of it. We may then use a jack to open the break in the middle 
bar a short distance, make the weld, and then slowly loosen the tension 
on the jack as the metal contracts. Or we may wrap wet cloths or 
wet asbestos or clay around the middle bar, close to the weld, make 
the weld and while making it keep cold water running on the material 
US ed — this method simply holds the expansion to a limited area and 
should be employed only when no other method is possible. Un- 
doubtedly the better method in nearly all cases is the preheating of 
the article or a portion of it, though in each case proper judgment must 
be exercised. 

The fact to bear strongly in mind and to understand thoroughly 
before proceeding to actual welding is, that expansion and contraction 
must always take place and that we cannot prevent it with jigs, vises, 
shafts or angle irons. We may offset its ill effects by one of the 
methods outlined in the preceding paragraph and we will do well to 
thoroughly digest this, since most failures in welding may be traced 
directly to lack of knowledge of expansion and contraction. 

CHEMICAL ACTION OF THE FLAME 

Metals are susceptible to certain chemical actions, especially 
under the influence of heat. Particularly, they have a high affinity 
for oxygen ; that is, oxygen, either from the flame, from the air, or 
from wet gas, may unite with the metal and form an oxide. This oxide 
is detrimental to the weld, exactly the same as iron rust, which is one 
form of iron oxide, weakens iron ; hence we must guard against 
oxidation. 

Since acetylene is rich in carbon and the presence of carbon in 
steel or iron makes them hard and brittle, the flame must be properly 
adjusted to prevent an excess of carbon being deposited in the weld ; 
in other words, to prevent carbonization. 

Oxygen also has an affinity for the carbon in iron and steel and 
the loss of it changes the character of the metal. This action, how- 
ever, is so like oxidation that we may consider it practically the same 
in guarding against it. 

MECHANICAL EFFECT OF THE FLAME 

Case hardened or tempered steel cease to be hard after being 
melted, as happens when a bond is made with the oxy-acetylene flame. 
In the welding of brass or bronze, we may melt out some of the alloy, 
changing the color and composition of the casting in the line of weld- 
ing. Copper may lose its ductility — cast iron become brittle. To a 



18 



THE IMPERIAL BRASS MFG. CO. 



large extent we may prevent many of these detrimental chemical and 
mechanical changes by proper selection and use of the welding rods 
and fluxes, plus proper use of the torch and careful heating and 
cooling. 



PREHEATING AGENCIES 

Since it is often necessary to preheat an article, either in sections 
or all over, to prevent breakage or distortion and in some instances 
also to prevent detrimental chemical actions, we must decide upon an 
agency to do this. 




PLATE 9 

The simplest form of preheating is undoubtedly a temporary fire 
brick furnace, with charcoal, as shown in Plate 9. But we may also 
use gas to decided advantage, if we are properly equipped with a 
blower to furnish air for it, or we may use kerosene oil. 

The choice of a preheating agency must be governed entirely by 
our needs. Any of the three methods are usable, but for reasons which 
are obvious, the oil or gas torch offers at times many advantages over 
charcoal, i. e., the ability to concentrate the flame when it is advisa- 
able to do so, as when only a section of a casting requires preheating, 
for example. We may also use charcoal in a hearth which we may 
construct ourselves, similar to Plate 10, covering the article with 
asbestos paper while heating and welding. 



THE IMPERIAL BRASS MFG. CO 




PLATE 10 

SLOW COOLING 
Care must also be exercised in cooling slowly to effect a uniform 
distribution of the heat in order to prevent breaks or strains and also 
for one other important reason later more fully described under Cast 
Iron. Sometimes we are able to use the preheating furnace for cool- 
ing, allowing the article welded to cool with the dying fire ; but a box 




•■ - v. > }■:. 



u' if -f'.'-VjA''"' 



PLATE 11 



20 



THE IMPERIAL BRASS MFG. CO. 



made of sheet iron, with seams welded, similar to Plate 11, and filled 
with a good non-conductor, such as asbestos, mica, or even ashes, costs 
little to make and the hot casting may be placed in it to insure even 
cooling, away from draughts. 

WELDING TABLES 
For welding small pieces or as an aid in securing the proper 
alignment of articles with flat surfaces, a table with a heavy cast iron 
top is indispensable. Such a table may be purchased from the Imperial 
Brass Mfg. Co. In addition to this, we should have a table with a fire 
brick top, the size of which will depend upon the kind of work handled, 
but which should be large enough to construct upon it temporary 
heating furnaces if we so desire. Such a table may be made from pipe, 
angle or channel iron, with all connections welded, as in Plate 12. 




PLATE 12 



CLAMPING DEVICES— TOOLS 
No specific advice can be given regarding shop equipment, as this 

will depend wholly upon the character of work to be welded. In some 

instances, we need nothing but the welding outfit. In others, we 

should have clamps to aid us in securing alignment, V blocks for the 

same reason in shaft welding, etc. 

A stationary grinder is a necessity both in preparing and finishing 

castings and a portable grinder may be classed as desirable in most 

cases but not essential. 

Asbestos paper, purchased cheaply by the roll, should always be 

on hand to shelter the castings from draughts while heating and also 

to protect the operator from intense heat radiation. 



THE IMPERIAL BRASS MFG. CO. 



21 



aids. 



Hammers, chisels, files, tongs, etc., are inexpensive but necessary 

REGULATION OF THE FLAME 
A B C D 




B C 

PLATE 13 



D 



A — Acetylene turned on with sufficient pressure, so that it blows away from 
the tip. This space depends upon the size of tip being used. On the No. 1 
the interval between tip and acetylene flame would be about re ; on the No. 10, 
34 of an inch. 

B — Oxygen partly turned on, united with the acetylene. The flame has begun 
to assume two different shapes and two different colors. The center flame is 
white and is shaped somewhat like a rosebud. Not enough oxygen has yet 
been given the acetylene and the flame is called carbonizing. 

C — This is the neutral welding flame. The rosebud cone of the upper figure 
has become blunt, with no ragged edges and of a beautiful blue-white color. 

D — An oxidizing flame — ruinous to welding. This is obtained by turning on 
too much oxygen and the cone has become shorter, of a darker, dirtier blue, 
and is more pointed. This view is exaggerated. The utmost care is necessary 
to guard against this flame, as even a slight excess of oxygen is detrimental. 

Imperial welding tips are marked on the flat sides with letters 
and numbers to indicate size of tips and pressure required in pounds 



22 THE IMPERIAL BRASS MFG. CO. 

and kind of gas. For example : Welding Tip No. 1 has on one side 
the figure (1), referring to size. On the next side is (A-2), which 
means a pressure of 2 lbs. of acetylene is required, and on the next 
side is (0-3), showing that 3 lbs. of oxygen are required, etc. 

The pressures to use on each tip, as explained above, are meant 
for the guidance of the operator. Conditions beyond the control of the 
manufacturer, such as the possible clogging or partial clogging of one 
or both of the gas lines, the slight derangement of the indicating 
gauge, etc., prohibit at times an exact compliance with these pressures. 
Since the adjustment of the flame is of the utmost importance in suc- 
cessful welding, we must learn the various forms the flame is known 
to take, so as to familiarize ourselves with the correct one by observ- 
ing its shape. 

In Plate 13 are four views of flames which we should earnestly 
study. Particularly watch at all times the character of the flame, 
remembering that even though adjusted properly at the START of 
welding, various conditions — expansion of the gases by the heat aris- 
ing from the weld, refrigeration of the gas caused by its release from 
pressure, enlargement or decrease in the sizes of the orifices by heat 
or dirt — tend to change the character of the flame DURING welding. 
With only one flame — the neutral — are we able to successfully weld. 
During the weld, then, we should find out if the flame is neutral by 
slightly opening the acetylene valve (or increasing the pressure on the 
acetylene by means of the diaphragm valve regulating screw) until 
the cone begins to assume the ragged shape shown in Plate 13-B (car- 
bonizing). 

We may, without particular harm, set the pressure on the regu- 
lating valves, say at ten pounds each, and adjust the flame by means 
of the valve on the torch, if we are using tips up to the No. 7 size. 
For the larger sizes, it will be better if we adjust the flame at the 
regulators. 

It will be noted there are two distinct shapes to the welding flame, 
the inner, short, very brilliant, and the other, long and of faint lumi- 
nosity. We call the inner the CONE and the outer the ENVELOPE. 
We will frequently refer to the CONE in our text; let us understand, 
then, that it is the short, brilliant flame shown at "C," Plate 13. 

BEVELING OR CHAMPFERING 

Since oxygen-acetylene welding is the joining of metals by fusion 
only and without hammering, it is necessary to bevel each edge of the 



THE IMPERIAL BRASS MFG. CO. 



23 




PLATE 14 
break on an angle of about 45 degrees, as in Plate 14, so that the heat 
of the welding cone? is sufficient in all places to flow the metal to- 
gether. On very thin sections, this beveling is not necessary, but the 
beginner should not attempt the welding of anything over one-eighth 
inch without first grinding the edges on about the angle stated. On 
heavy work, where it is possible to do so, this beveling or champ- 




PLATE 15 

fering should be done from each side, as in Plate 15. To do this, we 
may use the grinder, a hammer and chisel, possibly the drill press 
with a proper shape of drill, and in the case of wrought iron or steel 
over a quarter inch thick, the cutting torch. If this is done, it is well 
to thoroughly clean the edges to be welded, as well as a space each 
side of the weld, varying with the thickness of the casting, but ranging 
from one to three inches, to eliminate any possibility of dirt, including 
rust, from an outside source entering the line of welding. 



24 



THE IMPERIAL BRASS MFG. CO. 




PLATE 16 



Many times the shape of the article does not permit us to make 
this bevel all the way without danger of losing the alignment of the 
pieces. In a case like this, leave two or three places on the bottom of 
the casting to permit setting up, which is more clearly outlined in 
Plate 16. 

Beveling is very important ; unless we appreciate the necessity 
of doing it, good welding becomes extremely difficult and even very 
experienced operators will execute bad welds. 

HOW TO HOLD THE WELDING TORCH 




PLATE 17 



Theoretically, the proper way is to hold the torch as illustrated 
in Plate 17, so that the flame is directed in the line of welding, with 



THE IMPERIAL BRASS MFG. CO. 



25 



the work progressing AWAY from the operator. This method un- 
doubtedly is the most economical, since the ENVELOPE of the 
flame preheats the section to be welded and a weld made in this 
manner takes advantage of this preheating, which costs nothing. As 
we become expert, and where conditions permit it, this is the proper 
way to execute the weld. For the beginner, however, it is rather 
dangerous, since there is every likelihood of flowing the metal from 
the welding rod ON TO the line of welding, without getting it in 
fusion with it. 




PLATE 18 

Another method recommended by some is directly opposite to this 
idea, as in Plate 18. Here we work in the same direction as the line 
of welding, but our flame is pointing TOWARD the area already 
welded. In this manner there is much less chance of not properly 
fusing the metal, but this method not only does not take advantage 
of the preheating effect of the envelope, but keeps the cone on the 
welded section after it is welded, which is a serious objection. With 
all metals, we want to properly fuse the particular section we are 
working upon, but once fused, we must move on to the next spot 
immediately to prevent oxidation or burning of the material. 

Both of the above methods have a very serious disadvantage when 
working upon hot, heavy material, inasmuch as the channel made by 
beveling offers a pathway for the sweep of intensely hot waves and 
the position of the operator in these two methods places his hands and 
face directly over this channel. There is considerable discomfort in 



26 



THE IMPERIAL BRASS MFG. CO. 



some cases, even though the article is protected by asbestos paper; 
and since we cannot do proper welding unless we are watching the 
weld carefully, it seems to us that the best manner of holding the 
torch is as follows: 




PLATE 19 

Note carefully Plate 19. Here we are working at right angles 
with the line of welding, with the flame on an angle, pointing away 
from the line of welding. To prevent flowing hot metal ON TO 
comparatively cold metal, we would advise that the article welded be 
slightly raised on one end, so that the operator is always welding 
slightly UP HILL. Note carefully the angle of the HEAD of the 
torch in relation to the angle of the break or the sides of the metal 
being bonded. The torch is held so that the flame strikes BOTH 
edges at once. We may quite easily arrange the height of the weld- 
ing table or the position of the casting to effect this position without 
discomfort. MAKE CERTAIN THAT THE FLAME DOES 
STRIKE BOTH EDGES, since failure to do this means that the 
material from the welding rod is brought into fusion only with one 
side and merely sticks, without welding, to the other. 

CHOICE OF PROPER SIZE TIPS 



Thickness of 


i » 

32 


i « 


A" 


%" 


v± 


Vs" 
No. fi 


M" 


S A" 


%" 


l'and 
over 


Size of Tip to 
Use 


No. 1 


No. 2 


No. 3 


No. 4 


No. 5 


No. 7 


No. 8 


No. 9 


No. 10 



Above will be found a table giving approximately the size tip 
to use on mild steel plate of a given thickness. It will be under- 
stood that this table cannot be exact, but is meant as a help to the 



THE IMPERIAL BRASS MFG. CO. 27 

beginner. It is made up on the basis of welding without preheating 
and it will help us in arriving at a decision as to ABOUT which size 
to use. As we become more skilled, we may use a slightly larger tip 
than we do when learning to weld, and this results in faster welding, 
with a consequent saving of gas, since there is less radiation of heat, 
i. e., we bring the weld into fusion and get away quicker with a large 
tip than we do with a small one and there is less lost heat, due to the 
conductivity of the metal. More will be said about the choice of tips 
under the various Metal subjects. Let us carefully read the different 
subjects, whether or not we are interested in the actual welding of 
the metal covered, since the same GENERAL ideas of cast iron weld- 
ing, for instance, would apply to other metals and we will save our- 
selves considerable trouble by mastering the principles of welding by 
a little study first, and afterwards some practice. 

CAST IRON 

The welding of cast iron with the oxy-acetylene flame is com- 
paratively easy, if attention is paid to the simple rules, which to a 
large extent, have already been outlined. 

The cast iron in common use is known as "grey;" it is quite soft, 
easily machined and has a lower melting point than wrought iron or 
steel. It contains two kinds of carbon, combined and graphitic. If 
we change the graphitic into combined, we have white cast iron, ex- 
tremely hard, very brittle and practically impossible to machine. 
Because of certain chemical actions which take place when cast iron 
is melted, we may obtain a very brittle weld in this manner unless we 
pay strict attention to ALL of the following requirements : 

Heat or cool slowly. 

Use a proper welding rod. 

Employ a good flux. 

Handle the torch carefully. 
We have already learned the value of preheating to overcome the 
ill effects of expansion and contraction. Preheating is also an eco- 
nomical factor, since oxygen and acetylene are more costly than ordi- 
nary means of heating, and with cast iron it is essential that it be 
carefully heated and as carefully cooled to prevent hardening. 

The casting to be welded should be beveled as previously de- 
scribed. If entirely broken through and the ends are free to move, 
we should slightly separate THE EDGES before we start welding to 
allow for contraction. This separation, if we have properly champ- 



28 



THE IMPERIAL BRASS MFG. CO. 



fered the break, will be quite short — about l/32d of an inch will be 
found about correct. 

The utmost care should be exercised in preparation and in setting 
the article up to prevent its moving while it is being welded. Since 
we have a comparatively light edge from beveling, it is advisable to 
flow the metal together at this spot, "Tacking" it, as it is called in the 
welding shop. 

Especial care should be used to heat slowly, remembering that 
in the construction often employed, we will find heavy sections adjoin- 
ing light and the heavy section requires more heat than the light. 
Whatever means we may employ to preheat then, arrange to have the 
casting heated evenly and this can only be done by heating slowly. 

The size of the welding tip will be about the same as we would 
use for the same thickness of steel. While cast iron melts at a lower 
temperature than steel, its ability to absorb heat is slightly greater 
than steel and this will offset the lower melting point. 

The welding rod is furnished in three sizes ; we will choose for 
the one best adapted to the work that size which is somewhere near 
the same thickness of the metal — up to one-half inch in thickness. 
Beyond this thickness, we will use a rod of about ^ths and on extreme 
thicknesses we may tack two or three together, though this is rarely 
necessary. 




PLATE 20 
Now, with the welding rod in one hand and the torch, with the 



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Imperial Oxy-Acetylene Equipment 




No. 1 Imperial Welding Outfit with Truck 

UJiniiiDiiiniiiiiiiiiiiiiiniiiiiiiw 

NOTE — See catalog for full description and listing 



■iiniiiiiii 



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IMPERIAL WELDING i 



PATEr 



Type B— \ 




Type D — Combination 




r ™ r f 



Type E 



Www 



niiiiwiniinniiiiniiiiiniiiiiiniiiiinii!iiiniin 

NOTE-See catalog 



lillllllllliillillll 

D CUTTING TORCHES 



ENDING 




ing Torch 




[ding and Cutting Torch 




tting Torch 



IlillllllEI BEE! Illll 

description and listing 



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Imperial Oxy-Acetylene Regulators 




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NOTE — See catalog for full description and listing 



THE IMPERIAL BRASS MFG. CO. 



29 



flame properly adjusted in the other, and the flux can in convenient 
reach, we are ready to start welding. Presumably the casting is at a 
red heat in the furnace and we may protect ourselves from any ex- 
cessive heat by using the asbestos paper to cover such portions of it 
as may be necessary. 




PLATE 21 

Bring the welding flame down to the metal until the end of the 
cone is almost, but not quite, touching the edges, as in Plate 20. The 
welding rod is placed near the flame to slightly heat it — then it is 
dipped in the flux can and the flux picked up by the hot rod is placed 
in the spot the flame is playing upon. Usually this is sufficient to 
break the film of oxide and to cause the metal to flow together. Note 
that we have added no material from the welding rod as YET. Now, 
we melt the SIDES of the break and flow them towards the bottom, 
until the weld has the general appearance of Figure 21. Then we are 
ready to use the material from the welding rod, which should be kept 
in contact with the weld at all times to avoid loss of heat. REMEM- 
BER THAT THE ARTICLE AND THE WELDING ROD ARE 
THE SAME METALS, MELTING AT THE SAME TEMPERA- 
TURE. We must, then, keep the article and the rod in fusion at all 
times to effect a bond. Be very careful that the metal is actually 
melting while the rod is being added. 

Avoid the habit of pulling the torch away from the weld — rather 
use a slow circular movement which insures fusion and does away 
with loss of heat. Use the flux sparingly — never throwing it in with 
the hands — the amount picked up by the hot welding rod is sufficient 
at all times. At times it may be necessary to break the oxide by 



30 



THE IMPERIAL BRASS MFG. CO. 



stirring the molten iron with the rod and if the metal is very dirty, by 
pulling it out of the line of welding by means of the rod. 




PLATE 22 

Do not move away from the section being worked upon until the 
weld on that section is complete, as is shown in Plate 22. Never 
reweld without first grinding out the old material. Don't bring the 
cone in direct contact with the metal — hold it just a little distance 
away. 

As we progress with the welding, we note that the metal always 
does not flow where we want it to; i. e., where we are holding the 
flame. The force of the flame usually prevents this and we add the 
metal from the welding rod at a point a little distance away from 
where we actually want it to flow, and when we are ready to have it 
join the casting, we remove the flame from that point and swing the 
metal to the section desired by the circular motion described. 

Cast iron does not immediately solidify the moment the flame is 
removed — it remains liquid for some little time and this condition 
presents two difficulties ; one the danger of allowing this fluid metal 
to flow over, without bonding to other metal, and the other the col- 
lapsing of the weld. The first difficulty may be offset by watching the 
weld carefully and bringing all parts into fusion. The second one is 
usually experienced by beginners and is caused by their lack of knowl- 
edge of the metal and the force of the flame with the metal in a liquid 
condition is sufficient to cause the metal to collapse and create a hole. 
When we get this condition, it is sometimes discouraging, as our 
efforts to fill up the hole usually result in making it larger. 



THE IMPERIAL BRASS MFG. CO. 



31 




PLATE 23 



Remember that one of the reasons for the collapse is the force or 
velocity of the flame — the metal is fluid all the way through and this 
force is sufficient to let it drop. We must, therefore, have a solid base 
at all times, which may be secured by the circular motion of the 
welding torch — not keeping the flame in one spot too long. To fill a 
hole, work down the sides the same as we have done in starting the 
weld, then tip the torch on an angle as illustrated in Plate 23, being 
careful, however, to keep the metal in fusion all the time. The idea 
is, as may readily be seen, to divert the direction of the force of the 
flame. This same method is applicable where small sections may be 
missing. 

Where large sections are gone, we may make a rough pattern by 
the use of plaster paris and cast the desired design, or from useless 
castings of approximately the same thickness, break several pieces and 
by properly tacking them, form the general shape required. The user 
of the oxy-acetylene torch should realize that he has at his command 
a very powerful agent capable of replacing missing parts— a true 
"putting on" tool. 



32 



THE IMPERIAL BRASS MFG. CO. 



If we have carefully followed out the directions given for cast 
iron welding, we have a joint which is even stronger than the original 
article, and we can make it considerable stronger by adding additional 
metal to the line of welding, as we may desire, to strongly reinforce 
it. If we have had trouble, if the metal is hard, or if we get contrac- 
tion cracks, it is because we have not properly heeded the suggestions 
given. 

Since the welding of cast iron is usually repair work, the welder 
does not have a choice of conditions. He must take the article as it 
is, study carefully its construction with a view of determining the 
effects of expansion and contraction and plan to overcome them; he 
must use a welding rod which will prevent hardness; a flux which 
will make the metal fluid and remove the oxide ; and use judgment in 
slow and careful cooling. These are not difficult conditions — they 
simply call for that judgment which is sometimes called a knack. A 
little study means a good weld — the lack of knowledge means a failure, 
and since foresight is a great deal more valuable than second guesses, 
let us understand these conditions so we may intelligently use the 
welding torch. 

MALLEABLE CAST IRON 
This metal is originally white cast iron, very brittle and hard. 
By heat treatment, the carbon content is changed, and instead of the 
brittle casting, it becomes ductile, fairly soft and changes to a darker 
color. Just how far into the body of the metal this change penetrates 
depends upon the size of the casting and the length of the heat treat- 
ment, so that a malleable casting, as it is generally called, may be 
steel on the surface, a semi-steel part way through and white cast iron 
at the core — better outlined in Plate 24. 



Stee 



demi-steel 
White Iron 




PLATE 24 



THE IMPERIAL BRASS MFG. CO. 33 

Very small castings sometimes are steel all the way through and 
we may weld them without flux, using Norway iron or mild steel as 
the welding rod. 

In nearly all cases, however, it will be found that the casting is 
composed of different metals — if the break is examined, we can tell 
this by the different colors. It is obvious that such a casting cannot 
be welded, since it would be extremely difficult to determine just 
where one metal left off and another began. The practice of using 
cast iron as a welding rod on malleable castings is not a good one, 
since the bond is very brittle and in all cases where strength is de- 
sired we will better use manganese or Tobin bronze — in this way 
securing a brazed joint instead of a welded one, of a different color 
than the casting but with the factor of strength a big one. 

The break is prepared exactly the same as for any welding job, 
cleanliness in this instance being especially desirable, since the metal 
is not to be melted. Allowance should be made for the effects of 
expansion and contraction ; malleable iron is less liable to break than 
cast iron, since it is ductile, but will be distorted unless such provisions 
are made. Use for a flux the same powder that is used for brass. 

As with cast iron, do not let the end of the cone touch the casting, 
but hold it just a little distance away. Watch the metal carefully and 
when the spot the flame is playing upon reaches a bright red heat, 
bring the bronze welding rod, which has previously picked up some 
flux, down upon this section, being careful that the cone does not 
come directly in contact with the bronze rod. Bronze melts at a 
lower temperature than malleable iron and with the iron at a bright 
red heat, and with plenty of flux used, it will be found that the bronze 
attaches itself to the iron. We must not, however, MELT any portion 
of the malleable iron and we must not play the cone directly on the 
iron or on the bronze. 

STEEL AND IRON 

There are many different varieties of steel, but from a welding 
standpoint they may be classified by their carbon content. Those 
having a high carbon content are called hard steels ; those with a low 
carbon content, soft steels. Wrought iron may be treated the same 
as mild or soft steel. To be sure, there are various alloys, such as 
vanadium, tungsten, nickel, manganese, chromium, etc., but in general 
these alloys will not seriously bother us, except in special instances 
and we will not take them into consideration, but will keep in mind 
whether the steel is soft, medium or hard. 

Soft or mild steel is in the widest use. More than any other 



34 THE IMPERIAL BRASS MFG. CO. 

metal, the welder will have to study it, since from previous under- 
standing or training he has learned that it is the easiest metal to weld ; 
whereas, it is by all means the most difficult and frequent failures 
result if the operator lacks certain elementary knowledge of it. 

Mild steel is very ductile — it may be hammered cold or hot with- 
out fracture, and this fact is an invitation to the careless workman to 
disregard the effects of expansion and contraction. 

We should bear in mind, then, that while it may not break, it will 
bend or distort, unless we take into consideration expansion and con- 
traction, and we are very likely to have failures or leave a strain in 
the weld or in some section of the article welded, which will break 
while in use. Since the metal is ductile, it is not necessary at all 
times to preheat it in order to offset expansion and contraction — we 
may bend certain sections before welding, with a view of having the 
contraction straighten them and thus allow for contraction ; we may 
use water or wet asbestos, clay, etc., to LIMIT the expansion — these 
methods are sometimes essential, where we cannot preheat, due to 
size or location of the weld, but in all cases where we may do so, the 
proper way is to preheat. Where we cannot do so, we will choose one 
of the other methods, but ALWAYS we must allow for expansion and 
contraction. 

Previously we have spoken of the danger of oxidation and decar- 
bonization. The oxidation, or we might say burning, of steel is very 
rapid, if we in any way neglect essential requirements, chiefly the 
proper adjustment of the torch to secure a neutral welding flame, a 
welding rod without injurious elements and the proper handling of 
the torch. Decarbonization is caused in the steels but not particularly 
mild steel, if we are reasonably careful. But particular care must be 
taken to adjust the welding flame to secure a neutral flame and to 
keep it neutral during the welding. Make sure you understand this. 
PREPARATION OF THE WELD 

Particular care must be taken in beveling steel to see that the V 
is especially wide. We are not able to burn out this V with the torch, 
as we are sometimes able in other metals, since to do so means severe 
oxidation or burning. On metal under one-eighth inch no beveling 
is necessary. 

The proper preparation will depend largely on whether we are 
constructing or repairing. If we are welding new sheet metal, for 
instance, we may butt the edges and make what is termed a "flash" 
weld, using no welding rod. Such a weld will naturally not be as 
strong as the material, since it will not be as thick. 



THE IMPERIAL BRASS MFG. CO. 



35 




PLATE 25 



Or we may upset the edges, as shown in Plate 25, and these upset 
edges take the place of the welding rod and melt down, as shown in 
Plate 26. 




PLATE 26 

As the metal becomes thicker, this is impractical, and we then 
bevel and use a welding rod approximately of the same material as 
the metal welded, being sure it is of the right quality, however. 

No flux is necessary on mild steel and torch should be held in the 
position previously described, particular care being given to the neces- 
sity of having the flame directed to BOTH edges of the material. 



36 



THE IMPERIAL BRASS MFG. CO. 




PLATE 27 

Much of the mild steel welding done is impractical or impossible 
to preheat, and a frequent mistake of the beginner is to too quickly try 
and start fusion. To avoid this, we first play the torch in a gradually 
decreasing circle, as shown in Plate 27, with the end of the cone just 




PLATE 28 



THE IMPERIAL BRASS MFG. CO. 



37 



a short distance from the surface, until the metal becomes red in the 
vicinity of the weld for a distance about three times as wide as the 
metal is thick. 

Then we bring the cone down as shown in Plate 28 until the end 
of it just touches the surfaces to be joined. Note this carefully, since 
steel is the ONLY metal with which we bring the cone INTO 
ACTUAL CONTACT. On all other metals we hold the cone a little 
distance away. Do not make the mistake of bringing the tip of the 
torch to the metal — hold the torch so that the end of the cone just 
LICKS the surface. 




PLATE 29 

As the bottom of the bevel melts together, the welding rod is 
brought down until it touches that spot and a small portion of it is 
melted while it is in contact with the material, as in Plate 29. 

Now, we fuse this small portion to the material by a short circular 
motion, making sure that the flame actually comes into contact with 
every portion of it and that it is thoroughly fused to the material and 
that it has penetrated. As we finish the circular motion, we start 
melting the spot immediately adjoining. 

Unlike cast iron, steel does not remain a liquid — it solidifies al- 
most the instant the flame is removed, and it is for this reason that we 
are able to weld it in a vertical or overhead position, as well as 
horizontal. 



38 THE IMPERIAL BRASS MFG. CO. 

If there is an excess of sparks, the flame is improperly adjusted 
and contains an excess of oxygen. If the metal melts too rapidly and 
is difficult to control, the tip is too large. If it does not keep in fusion 
and there is difficulty in getting the welding rod material to actually 
fuse to the article, the tip is too small. The beginner will be troubled 
with the welding rod sticking to the metal — don't attempt to pull it 
away ; let it stay there until it is necessary to melt a portion of it in 
the weld. 

Steel welding on a commercial scale should never be attempted 
until after the operator has proved to his own satisfaction that the 
weld is strong by welding together mild steel plates of one-eighth to 
one-quarter inch, sawing them through the weld to make sure that the 
material is really bonded and testing them by bending back and forth 
in a vise. 

The practice of twisting several pieces of wire together to form a 
welding rod is not a good one, since this exposes more surface to 
oxidation or burning and for the same reason have the rod in contact 
with the material welded as it is added to the weld, so the article will 
prevent burning by its ability to conduct the heat away from the rod. 

In welding two pieces of unequal thickness, we must bear in mind 
suggestions previously given — that the large piece requires more heat 
than the smaller one, and that care must be used to cool equally to 
prevent strains. 

MEDIUM AND HARD STEELS 

With the increase of carbon content, welding becomes more diffi- 
cult, yet by no means is it impossible, even on those steels containing 
a large percentage. Whether or not we should employ the oxy- 
acetylene flame depends entirely upon our skill and the use of the 
article welded. Crank shaft welding is usually practical, if we are 
proficient ; yet most crank shafts have a high carbon content. But it 
is by all means the best practice to become a good mild steel welder 
before attempting higher carbon steels. 

To prevent, as far as possible, decarbonization, we should use the 
cast iron flux on steels of high carbon and a welding rod of a higher 
carbon content if we want about the same hardness. If the bond be 
one which will bend without harm, use a mild steel welding rod, since 
it is easier to make a weld of this character. Common steel may be 
welded to tool steel — for instance, an auto spring may be welded with 
high carbon steel, if retempering is necessary ; but if broken on the 
end, it may be welded with mild steel with good results. The welding 



THE IMPERIAL BRASS MFG. CO. 39 

of steels of high carbon call for a great deal of skill and it is impos- 
sible to lay down any hard and fast rule governing all cases. After 
we have become good mild steel welders, we are usually able to deter- 
mine whether we should or should not weld steels of higher carbon. 

ALUMINUM 

While aluminum has a melting point less than half that of steel, 
its conductivity is over three times as great, so we use a tip about the 
same size for this metal as we do for steel, and because of this con- 
ductivity, we should realize that the effects of expansion and contrac- 
tion must be particularly guarded against, since there is a large area 
which is heated and expanded and consequently a large area which 
must cool and contract. 

The manufacture of sheet aluminum articles is daily becoming 
larger — the requirements in preparation practically the same as for 
iron or steel sheets, with the addition of a proper flux. 

Aluminum castings vary in their composition, and success in weld- 
ing them will depend somewhat upon the alloy used. Copper increases 
the strength, but machine work is made difficult ; many times there is 
a large percentage of zinc, which makes machine work easy, but the 
casting is more or less brittle. An aluminum case, welded without 
attention paid to the effects of expansion and contraction, may distort 
or it may break — it depends upon the alloy used. The first considera- 
tion in aluminum repair work is expansion and contraction. We have 
previously studied this principle and should realize its importance, 
remembering that with aluminum the shrinkage is a great deal more 
than the metals we have already dealt with and warpage or breakage 
are certain unless we understand it. Plan, then, to heat and cool 
slowly and evenly. 

Oxidation takes place very easily — more so than with other 
metals — and this oxide has a very high melting point. As the metal 
comes to the melting point, this oxide forms a film which prevents 
the edges flowing together and it must be destroyed before a bond can 
be effected. The method generally practiced by experienced welders 
is to destroy this oxide by means of a small iron rod or paddle and 
the edges joined by puddling the metal with this rod. This method 
is the cheapest, but it calls for the exercise of considerable skill and is 
not so effective as the destruction of the oxide by a flux, since it intro- 
duces the oxide into the weld. 



4Q THE IMPERIAL BRASS MFG. CO. 

Beveling aluminum is not so important as other metals, since the 
action of the flame causes the edges to slightly draw apart from each 
other. At this moment, the welding rod coated with flux, the same as 
with cast iron, is added, the flux chemically removes the oxide and the 
edges are bonded and material added from the rod at the same time. 

With aluminum, we are especially likely to cause the metal to 
collapse because the heated area, due to the high conductivity, is large 
and the metal is without "strength" when it is very hot. For this 
reason, it is advisable for the beginner to make a mould consisting of 
approximately two-thirds asbestos fibre and one-third plaster paris to 
back up the broken section. Have this mould about one inch thick and 
let it dry thoroughly before starting to weld. Asbestos paper or 
ordinary paper may be put between this mould and the case if desired 
and if this will help in keeping dirt out of the weld. 

How hot shall we preheat aluminum castings? It depends upon 
the alloy used. Ordinarily, a safe rule to follow is to stop heating 
when the casting gives off a dull sound when tapped lightly with a 
hammer. We can tell little by its color, as we can with iron and steel 
and even with the welding flame playing upon the break, it gives 
practically no warning that it is in a melting condition, other than 
when it is ready to add the flux and welding rod, it has a wrinkled 
appearance, dull grey in color. 

Special care must be given to even heating, since most castings 
have bosses thinner or thicker than adjoining sections and we are 
likely to melt the thin part unless we particularly guard against it, or, 
on the other hand, not give the heavy section enough heat and so 
cause an unequal expansion. 

Remember that aluminum must be carefully supported when pre- 
heating, since it is very brittle when hot, and as well keep it protected 
from draughts, as with other castings. 

Aluminum is not a difficult metal to weld — the difficulty lies in 
properly taking care of expansion and contraction, and if we study 
this subject carefully, we will avoid many of the failures of the 
beginner. 

In finishing the welded section of an aluminum casting, the ordi- 
nary wheel quickly fills up with chips. If this wheel is kept well 
oiled with a heavy lubricant, to a large extent this will be overcome. 
Ordinary files are useless and a Vixen should be used. 

COPPER 

Copper conducts heat more rapidly than any other commercial 



THE IMPERIAL BRASS MFG. CO. 41 

metal. It will oxidize very easily and this oxidation is not easily 
apparent to the operator, but the weld becomes very brittle. The 
melting point is under that of steel and iron, yet because of its high 
conductivity a larger tip for the same size material is necessary. Cold, 
copper is very ductile ; hot, it is brittle ; so care must be used in its 
welding, since at a high heat it is very likely to fracture, either at the 
weld or some distance away, since the heat is conducted so rapidly 
that the temperature of the metal some distance from the weld is but 
little less than at the weld. 

The metal should be prepared for welding the same as others — 
the V properly made, and the metal thoroughly clean. Besides the 
advantage of preheating to prevent contraction cracks or strains, 
owing to the high conductivity of copper, it will cheapen the welding 
operation considerably to heat it by other means than the oxy- 
acetylene flame. 

The welding of copper is quite difficult to realize and maintain 
ductility. A special welding rod is necessary containing an element 
opposing the action of oxygen on the copper and a flux for the same 
purpose as well. The cone should not come in direct contact with 
the metal at any time. 

For repair purposes, it is sometimes impossible or impractical to 
weld the break, and we then braze it, either with brass or bronze, 
using the brass flux for this purpose and following the same general 
directions as for brazing malleable iron. 

BRASS AND BRONZE 

Brasses and bronzes are composed of copper, with lower melting 
metals as alloys, zinc, tin, etc. Since these metals have different melt- 
ing points, considerable care must be exercised in welding not to 
change the character of the metal too much by burning out these 
alloys. 

The metal should be prepared the same as any other, with par- 
ticular care in setting up to prevent moving while being welded and 
to prevent collapse of the heated area. The metal should not be 
brought to fusion by bringing the cone in contact with it, but as 
with copper, the end of the cone should be slightly above the metal. 
For repair purposes, Tobin bronze or brass should be used for the 
welding rod — for foundries or in manufacturing where the weld must 
be practically the same color and the same material as the metal, more 
judgment is necessary in the choice of the rod, with a view of replac- 



42 THE IMPERIAL BRASS MFG. CO. 

ing, by means of the material in the welding rod, those metals burnt 
out of the line of welding by the flame. 

MISCELLANEOUS METALS 

Galvanized Iron — Cannot be welded, since the iron is covered 
with and to a greater or less extent impregnated with, a lower melting 
metal. 

German Silver — In many cases considered unweldable, due to its 
absorption of gases. For practically all commercial purposes, it may 
be bonded, using the same flux as for brass and a strip of German 
silver for the welding rod. Especial care must be given to expansion 
and contraction. 

Nickel — Extremely difficult to weld, but in many cases not im- 
possible. Anodes, used in nickel plating, may be fused together with- 
out flux and while there are considerable blow holes in the bond, the 
conductivity is little affected. Where a bond is required free from 
blow holes, it is possible to effect it by a combination of the black- 
smith weld with oxy-acetylene. 

White Metal — Castings used for die moulded purposes usually 
are composed of aluminum, tin and zinc in varying proportions, but 
nearly always with the lower melting metals in the larger proportion. 
While the castings have a good deal the same appearance as alumi- 
num, they are considerably heavier. They may be considered 
unweldable. 

Lead — Is perfectly feasible. The objection here is on the ground 
of heat ; i. e., the oxy-acetylene flame is too hot. This merely calls for 
speed on the operator's part and this metal is easily joined. The most 
successful flame for lead burning, however, is oxygen-hydrogen, for 
which special apparatus is furnished. See Page 52. 

Different Metals — Sometimes we are required to bond two differ- 
ent metals. Cast iron may be welded to iron or steel, for instance. 
The bond is brittle, to be sure, but sometimes this is not an objection. 
Some authorities recommend the use of Norway iron as a welding 
rod, but we would prefer using cast iron. 

Copper may be bonded to cast iron or steel, with copper used as 
a welding rod. Brass to copper, using brass as a welding rod, etc. 



THE IMPERIAL BRASS MFG. CO. 43 

FIGURING COSTS 

The high pressure oxygen gauge is registered in pounds. All 
oxygen cylinders are charged to a pressure of 1,800 pounds and at 
that pressure contain 100 cubic feet or 200 cubic feet, depending upon 
the size used. The pressure, however, is the same in all cases. 

The Imperial torch uses practically equal volumes of oxygen and 
acetylene, so it is only necessary to determine the cubic feet of oxygen 
used and estimate the same number of cubic feet of acetylene to 
determine cubic feet of both gases. 

As we know the cost per foot of each, F. O. B. the factory, it is 
necessary only to add freight or expressage to find out the cost per 
foot in the shop, and we are then in a position to figure exactly the 
cost of both gases on any job. 

The gauge pressure on the acetylene cylinder DOES NOT indi- 
cate cubical contents. As acetylene is dissolved in acetone, the con- 
tents of the cylinder varies with the purity of the absorbent and its 
volume. Temperature is also an important factor — in the winter a 
full cylinder will register, say, 150 pounds, and in the summer may 
register 300 pounds. We can determine the contents by weight, as 
there are 11% cubic feet of acetylene in a pound. If a cylinder weighs, 
when received, 160^ pounds and when empty 145 pounds, we have 
used 15^2 pounds of gas. Multiplying this by 14^ we have 22434, 
which is the number of cubic feet. 

This procedure is not necessary to estimate costs, since we can 
figure acetylene consumption by our oxygen gauge reading. It is 
advisable at intervals, at least, to check up the invoices in this manner 
to see we are getting the exact amount of gas for which we are paying. 
On Page 44 is a suggestion for a cost card, the principles of which 
may be adapted to your particular requirements. Overhead is largely 
a matter of local conditions, but in a repair shop it would be wise to 
figure this overhead at a fairly high percentage. 



44 



THE IMPERIAL BRASS MFG. CO. 



SUGGESTION FOR COST CARD 



Oxygen gauge, start. . . . 


1800 


lbs.= 


=100 cu. ft. 


Oxygen gauge, finish. . . 




900 


lbs.= 


= 50 cu. ft. 


Oxygen used 




900 


lbs.= 


= 50 cu. ft. 


Acetylene used — 










50 cubic feet 


@ 


2% 




$1.25 


Oxygen used — 










50 cubic feet 


@ 


2 




1.00 


PREHEATING COST 






Charcoal 










Gas, y 2 hour, 2 burners. 


@ 


60 




.30 


Kerosene 










LABOR (Preparing)— 




1 hour 30 min 


@ 


60 




.90 


LABOR (Welding)— 










1 hour 30 min 


@ 


60 




.90 


LABOR (Finishing and 


testing)- 








1 hour min 


@ 


30 




.30 


RODS— 










Lbs. Steel 


@ 








15 Lbs. Cast Iron . . . 


@ 


10 




1.50 


Lbs. Bronze 


@ 








Lbs. Copper 


(a) 








Lbs. Aluminum . 


@ 








FLUX— 










^2 Cans Cast Iron. . . 

M 
« 
M 
« 


@ 


50 




.25 






Total 


$6.40 


REMARKS 













THE IMPERIAL BRASS MFG. CO. 



45 



CUTTING WITH IMPERIAL APPARATUS 

ov- 




Imperial Cutting Torch — Type E 

A — Acetylene Inlet. AV — Acetylene Valve. C — Lever Operating Valve 
for Oxygen Cutting Jet. D — Thumb Screw. F — Removable Housing that 
protects Cutting Tips. O — Oxygen Inlet. Nos. 2, 3 and 4 are Cutting Tips. 

SETTING UP APPARATUS 

The same general care is required for the cutting equipment 
which has been outlined for the welding apparatus, particular care 
being given to tight hose connections and valves which will not leak, 
since the oxygen is used at a higher pressure and a leak, in combina- 
tion with the flying sparks, is likely to cause a serious burn. 

The oxygen hose is attached to the upper tube, as with the weld- 
ing torch, and the acetylene to the lower. The pressure used on the 
oxygen line is considerably higher than in welding, since we need an 
excess of oxygen, which is conducted through an inner tube, to 
OXIDIZE or burn the metal. 




ess. 



PLATE 30 
SPECIAL IMPERIAL TIPS FOR STRAIGHT CUTTING 

For cutting of plates, I-beams, etc., where the line of cutting is always 
straight, we have designed a special flat tip, with only two preheating flames 
(Plate 30). By this method a smaller surface of the metal is being preheated, 
a narrower, smoother cut results and a considerable amount of gas is saved. 



46 



THE IMPERIAL BRASS MFG. CO. 




PLATE 31 

SPECIAL IMPERIAL TIP FOR RIVET CUTTING 
For rivet cutting we furnish a flat tip slightly curved, which allows quick 
and clean cutting of rivets without injury to the plate. 

These tips are furnished on application with regular Cutting Outfits. 

SELECTION OF CUTTING TIPS 
Each Imperial cutting tip is marked on the flat sides with letters 
and numbers to indicate size of tip, thickness of metal it will cut, 
pressure in pounds and kind of gas. For example : Cutting Tip No. 1 
has the figure 1 on one side, meaning size No. 1 ; on next side are Y% 
and 3, meaning it will cut wrought iron or steel from y%" to 3" in 
thickness ; on the next side is A-15, meaning the small acetylene gauge 
should register 15 lbs., and then the marking O-70, which means the 
small oxygen gauge should register 70 lbs. 

Note that the markings A-15 and O-70, referred to above, indicate 
the MAXIMUM gas pressures needed for cutting the thickest metal 
that particular size of tip is intended for. To illustrate: When cut- 
ting y^" or thinner metal with the No. 1 tip, an acetylene pressure of 
about 10 lbs. and an oxygen pressure of about 40 lbs. are required. 
These pressures are varied according to the thickness of the metal and 
the conditions to be met. 

Select the proper size of cutting tip according to the thickness of 
metal to be cut as follows : 



Thickness of Metal 


...: 34" to 3" 


3" to 6" 


6" to 9" 


9" to 12" 


Size of Tip to Use 


...1 No. 1 


No. 2 


No. 3 


No. 4 



After screwing the tip into the torch, screw the housing (F) down 
and be sure the face of the housing is flush with the end of the tip. 

The preheating flame is adjusted exactly the same as for welding, 
but in this case we have six small flames instead of one and we must 
control the adjustment by means of the shut-off valve on the torch. 
The valve with the lever handle is the one which controls the inde- 
pendent oxygen supply, the one which does the cutting, and which 
comes down in the center of the tip. This is a diaphragm control, 
shutting off the gas when the lever is pressed down and open when 
the lever is allowed to spring up. A small knurled wheel controls the 



THE IMPERIAL BRASS MFG. CO. 



47 



distance this lever moves and may be adjusted by the operator. A 
cutting torch is simply a welding torch with an added tube through 
which comes oxygen alone under pressure to oxidize the metal. 




Imperial Combination Welding and Cutting Torch 

A — Acetylene Inlet. B — Valve for Oxygen Cutting Jet. AV— Acetylene 
Valve. OV — Oxygen Valve. F — Removable Housing that protects Cutting 
Tip. No. 5 Tip is attached to Welding Head. O— Oxygen Inlet. Nos. 1-10 
on right are the Welding Tips. Nos. 1 and 2 on left are Cutting Tips. Cutting 
Attachment removed is shown at top of illustration. 

In combination with the welding torch, the Imperial Brass Manu- 
facturing Company also furnish an attachment for cutting, which can 
be attached to the welding torch, as shown in Plate 32. Here the 
lever control is supplanted by a push button, the principle of which is 
exactly the same as the lever control of the cutting torch. 

In planning the job, have the tanks firmly secured to prevent 
tipping over and hose BEHIND you so as to protect it as far as 
possible from damage due to flying sparks. Make certain also that the 
hose is not in a location where it may be cut or otherwise damaged. 
PRINCIPLE OF CUTTING 

Beginners often mistake cutting for melting. Since the only 
visible agency to do work is the flame, it is assumed that the flame is 
melting the iron or steel. This is not so, however. Previously we 
have spoken of oxidation and how we must guard against it in weld- 
ing; that oxidation is the burning of a metal and takes place by 
oxygen uniting with the metal and forming an oxide. Cutting, then, 



48 



THE IMPERIAL BRASS MFG. CO. 



is simply the rapid oxidation or burning of the metal and the flame is 
used merely to get the metal hot enough so that it will oxidize quickly. 

Since all metals are subject to oxidation in welding, it is natural 
to assume that all metals could be cut by means of oxygen from the 
cutting torch ; but this is not so, and we are limited to those metals 
where the oxide is of a lower melting point than the metal itself, this 
being the case in wrought iron and steel. Other metals, such as cast 
iron, aluminum, copper, brass, etc., cannot be cut. 

The flame is of use simply to get the metal hot enough so that 
oxidation takes place rapidly ; the oxide having a lower melting point 
than the metal, runs off the metal and leaves a new surface exposed 
to the cutting jet of oxygen. Once started, this oxygen jet theoretic- 
ally should be sufficient to keep up oxidation, since there is consider- 
able heat created — the oxygen being the supporter of combustion and 
the metal the fuel — in other words, the metal is burnt up, but because 
the stream of oxygen is small, this burning is confined to a narrow 
area. We need the flame because other influences, scale, dirt, the air, 
sand, blowholes, etc., may stop this oxidation and the flame then heats 
the metal to a sufficient point to again start oxidation. 




PLATE 34 
HOW TO CUT 

When the flame is adjusted, as described above, hold the torch as 
shown in Plate 34, the left hand grasping it well toward the head and 



THE IMPERIAL BRASS MFG. CO. 



49 



the right hand on the handle with the fingers controlling the lever 
valve. The elbow or forearm should rest on the material being cut 
whenever possible to steady the torch. When we are cutting free 
hand, that is without the wheel guide, IT IS DESIRABLE TO AR- 
RANGE TO CUT EITHER RIGHT TO LEFT OR LEFT TO 
RIGHT — not toward or away from the operator. 

Start on an edge — not in the center of a plate — whenever it is 
possible. Now hold the flame on the edge until it gets to a white heat ; 
release the lever valve and the oxygen immediately starts burning the 
metal. Hold the torch steady until the cut goes through — then move 
the torch along the line to be cut with a steady movement — not a 
jerky one. WATCH THE DIRECTION OF THE SPARKS. If 
they fly in the direction as shown in Plate 35, the cut is not going 
through. At the start, they should appear about as shown in Plate 36. 
Then the torch head is slightly inclined TOWARD THE DIREC- 
TION WE ARE CUTTING. 




PLATE 35 



50 



THE IMPERIAL BRASS MFG. CO. 




PLATE 36 



Previously we have remarked that various reasons cause the 
stopping of oxidation. The chief reason (for beginners, at least) is 
the unsteadiness of the hand. Just the moment this oxidation stops, 
use the right hand to close the lever valve on the oxygen supply, then 
start heating an edge exactly the same as in the beginning of the cut 
and when at the white heat again release the lever valve and start 
cutting. 

When the cut to be made must be reasonably smooth, use the 
wheel guides, and if a straight line must be followed, clamp a suitable 
bar of metal to the article to be cut, as shown in Plate 37. 



THE IMPERIAL BR ASS MFG. CO. 



51 




PLATE 37 



GENERAL HINTS ON CUTTING 

Hold the flame so that the end of the cone just licks the metal — 
don't attempt to plunge it down into the cut. 

When cutting two plates or more, or where there is a lap joint, 
remember that there is more or less of an insulation (air, dirt, etc.) 
between these plates and that the oxidation cannot be as fast as where 
only one thickness is cut. THE SLIGHT TIPPING OF THE 
TORCH TOWARD THE DIRECTION TO BE CUT IS A HELP 
IN CUTTING MORE THAN ONE THICKNESS. 

Remember that the flame does not do the cutting — therefore, 
work with the smallest flame possible — it means a neater cut. 

Keep the oxygen pressure as low as possible and yet maintain 
speed. A high pressure is spectacular and there are a great number 
of sparks, but it is not economical and a wider scarf is made. 

Don't use the torch with greasy gloves — a spark in combination 
with a leak on the oxygen supply will badly burn the hand. 

If a cut must be started in any place except on an edge, drill a 
hole or use a cold chisel and a hammer to roughen up the surface, the 
idea being to get an edge to quickly start oxidation. 

POINTS TO BE OBSERVED 

Never use oil or lubricant of any kind on tank valves, gauges, 
regulators or other fittings, as this may result in spontaneous com- 
bustion and explosions. 

Be careful that there are no leaks in any of the connections, or in 
the rubber tubing, and that the torch tip is free from obstruction. 



52 THE IMPERIAL BRASS MFG. CO. 

Always have an ample supply of gases, before commencing a job, 
as it is injurious to stop in the middle of the work. 

It is necessary to wear tinted glasses or goggles to prevent eye 
strain. 

In doing heavy work, if the burner is used continuously for a 
long time, or held in a confined space, it will become heated. In such 
cases, turn off the gases and dip the torch head into cold water. 

When working inside a boiler or tank, or any small enclosure, 
two operators should be employed, so that one will be available to 
quickly turn off the gases in case of accident, such as the bursting of 
the hose. 

No one but a thoroughly instructed, experienced operator should 
attempt boiler welding. 

We believe the time will soon come when the officials of shops 
will require a Certificate of Competence from every operator who is 
entrusted with that kind of work, and The Imperial Brass Manufac- 
turing Company is opening a school with competent teachers to 
qualify students for every kind of welding and cutting. 

In very heavy welding, two operators should be used, so that one 
can relieve the other, and the work continued until finished without 
interruption. 

An excessive discharge of sparks indicates that too much oxygen 
is being used, and that the metal is being burned or oxidized. In very 
heavy welding, there will, of course, be a considerable volume of spark 
even when the flame is neutral. 

Butt welding is preferable to lap welding and easier to perform. 

In clearing the torch tips, do not use steel ; employ copper or some 
other soft metal. 

Never tighten up regulating screws on either regulator except 
when tank valves are open, as otherwise you might distort the 
diaphragm. 

OXY-HYDROGEN PROCESS 

The foregoing directions are applicable specially to the use of 
oxygen and acetylene gas for welding and cutting. 

Imperial Torches are also adapted for the use of hydro-carbon 
gases and of hydrogen in connection with oxygen gas for welding and 
cutting. 

Special tips and special regulators are furnished for these pur- 
poses with Imperial Equipment on request. 

We do not recommend welding of steel above *4" and of cast iron 



THE IMPERIAL BRASS MFG. CO. 53 

above Y^" in thickness with, anything but acetylene and oxygen, but 
for welding of light sheet steel of No. 16 gauge and up, light cast iron 
and especially aluminum, the oxy-hydrogen process offers many ad- 
vantages provided the hydrogen can be purchased at a reasonable 
price. 

The oxy-hydrogen flame having a temperature of about 4,000° F., 
the metal is not so easily burned, and as hydrogen contains no carbon, 
the weld is softer and very uniform. 

In welding with oxygen and hydrogen, the torch has to be held 
somewhat further away from the work than is practiced in oxy-acety- 
lene welding, because the flame is not so pointed and less concentrated. 

When a black spot appears in the weld, it proves that the torch 
is too near the work and the distance has to be slightly increased. 
Otherwise the same directions given in the former chapters on oxy- 
acetylene welding apply also on oxy-hydrogen welding and an experi- 
enced oxy-acetylene operator will soon become proficient in this 
branch of his trade. 

For cutting of steel and wrought iron, the oxy-hydrogen flame is 
decidedly superior to the oxy-acetylene flame. Hydrogen does not 
deposit carbon products in the seam, it lessens the formation of slag, 
therefore a much cleaner and smoother cut results and much thicker 
material can be cut with the same amount of gas. 

A drawback to the novice in the use of hydrogen is the circum- 
stance that the hydrogen flame is not easily visible and it seems harder 
to properly adjust the flame. However, Imperial tips are all marked 
with the required gas pressures and the operator quickly gets used to 
the different conditions. 

CARBON BURNING 

We have already learned that oxygen and carbon have a great 
affinity for each other ; that is, that oxygen will unite with carbon very 
easily. Carbon in a cylinder of a motor is caused by imperfect com- 
bustion — it may be there because the carburetor was not adjusted 
properly to give sufficient air or it may be because too much oil was 
used in proportion to the air. If the motor had received enough air, 
it would not be there, and since the element in the air necessary to 
completely burn it is oxygen, we may remove it quite easily by the 
use of oxygen. 



54 



THE IMPERIAL BRASS MFG. CO. 





PLATE 38 

Imperial Decarbonizing Outfit 

A — Oxygen Tank Valve. B — Tank Coupling. C — Pressure Gauge show- 
ing pressure delivered to Torch. D — Regulating Screw. E — Hose Connection. 
F — Trigger Valve. G — Hose Connection. H — Flexible Copper Tip. 

THE APPARATUS 

The Imperial Carbon Burning Equipment consists of one oxygen 
regulator with gauge and the decarbonizing torch with hose. 

REMEMBER THAT OXYGEN ALONE IS NECESSARY TO 
DO CARBON BURNING — NO ACETYLENE BEING EM- 
PLOYED. 

Connect the oxygen regulator to oxygen tank and the hose at 
one end to outlet E of the regulator and at the other end to the carbon 
burning torch G. 



THE IMPERIAL BRASS MFG. CO. 55 

Now, with the motor running, shut off the gasoline and allow the 
engine to run down. If the engine is particularly dirty, it may be 
advisable to protect the carburetor and pan by placing some asbestos 
paper at points to prevent fires from flying sparks. 

Remove spark plugs from cylinders — not the valve caps. Crank 
the motor until the cylinder to be started upon has the piston at the 
top, with both valves closed. 

Set the pressure on the regulator at about fifteen pounds and 
PARTIALLY depress the lever on the handle of the carbon burner. 

Use a wax taper or drop a lighted match into the spark plug 
opening of cylinder, at the same time directing the copper tube of 
the carbon burner at that point. This ignites the carbon, and if it is 
not too dry, the oxygen should thereafter be sufficient to completely 
consume it without again lighting it. At the start, particularly if the 
cylinder is oily, there will be some flame as well as considerable 
sparks. Hold the pressure down until the flame has practically dis- 
appeared, press down the lever all the way and move the tubing back 
and forth around the walls until sparks stop. 

Sometimes the cylinder is very dry and the carbon is rather 
difficult to burn. This can be more or less determined by the appear- 
ance of the spark plug. If it is dry, squirt about a teaspoonful of 
kerosene into the cylinder, spreading it over as large a surface as 
possible, to AID the burning. 

The tube is flexible and may be bent as desired to reach any 
portion of the cylinder. Actual contact with the carbon by the tube 
is not necessary to consume it — carbon burns in an atmosphere of 
oxygen after it is ignited. _ 

The only possible danger to the cylinder, valves or piston is a 
too high pressure of oxygen on an extremely oily cylinder — there 
would be considerable heat generated in this instance. Hold the 
pressure down, then, until the flames have gone and sparks only are 
being thrown out before opening the lever on the handle full. 

When through cleaning, it is desirable to remove the valve cap 
and blow out any solid particles there may be present ; these solid 
particles cannot be carbon, but may be graphite, pieces of iron, etc. 
The appearance of the cylinder will be considerably improved by 
swabbing off the top of the piston and valves with an oily rag. 

Carbon burning is a very practical solution of carbon deposits — 
care and horse sense must be applied, however, though the process 
calls for no particular degree of skill. 



56 THE IMPERIAL BRASS MFG. CO. 

With every Imperial Welding Outfit a decarbonizing torch is 
furnished. For removing carbon from engine cylinders it is only 
necessary to connect this torch with the regular oxygen hose and to 
follow otherwise the directions given above. 



INDEX 



Beveling 22 

Carbon Burning 53 

Care of Apparatus 7 

Champfering 22 

Contraction of Metal 15 

Costs, Figuring 43 

Cutting 45 

Expansion of Metal 15 

Flash Back 13 

How to Hold Torch 24 

Oxy-Hydrogen Process 52 

Regulation of Flame 21 

Regulators, Acetylene 12 

" Oxygen ■ 8 

Tips, Selection of . 26 

Torch, Combination • 47 

Cutting . 45 

Welding 12 

Welding, Aluminum • 39 

Brass and Bronze 41 

Cast Iron 27 

Copper • ■ • 40 

Malleable Iron 32 

Medium and Hard Steel 38 

Miscellaneous Metals 42 

Preparation for 34 

Steel and Iron 33 



